Land mobile radio communication systems and cellular radio/telephone communication systems (communication systems) are known to include a plurality of communication units, a limited number of communication resources, broadcast units, and a resource controller. Communication units, which may be portable, mobile, or cellular radio/telephones, communicate voice or data information to other communication units or landline communication units via a communication resource and a broadcast unit. For a communication unit to be allocated a communication resource, the unit sends a request to the resource controller, wherein the request indicates that a communication resource is desired and what it is desired for. For example, if a communication unit in a trunked communication system desires to place a talk group call, the request will contain the communication unit's individual identification code and a message indicating that the communication resource is needed for a talk group call. Upon receiving the request, the resource controller processes it by determining whether the communication unit is a registered user of the system and whether the communication unit can request a talk group call. When the resource controller answers both of these questions in the positive, a communication resource is allocated to the communication unit for the talk group call.
The unit may request many other features that a communication system offers. For example, the communication unit may request interconnection calls (i.e. a telephone call through a public telephone switching network), private calls within the communication system, data transmissions, such as a facsimile transmission, secure transmissions, and many other special services. Each of these features are offered to subscribers (users of a communication unit) of a communication system for a fee. As would be expected to provide all, or even a few, of these features, a communication unit is a complex piece of equipment composed of several operational platforms, modules, and/or printed circuit boards.
In an effort to save research and development (R & D) funds, a less scrupulous manufacturer might be inclined to take the operational platforms, or the circuitries contained thereon, from reputable manufacturers and use them in their own products. In addition, the less scrupulous manufacturer may offer services, without the authorization of a reputable manufacturer, to subscribers that upgrade a communication unit having a limited set of special features to a communication unit that offers substantially all of the special features available. In either case, the less scrupulous manufacturer can offer identical products, or upgrade services, at a lower price than the reputable manufacturers because it didn't have the R & D expenses, thus taking market share away from the reputable manufacturers.
In addition to taking market share away for communication units, the less scrupulous manufacturer may also take operational platforms, or the circuitries contained thereon, of a broadcast unit of the reputable manufacturer. With the operational platforms, or the circuitries, of broadcast units, the less scrupulous manufacturer can offer an entire communication system at a reduced price and thus take further market share away from the reputable manufacturer. In order to minimize the market share loss, many reputable manufacturers protect their products, including communication and/or broadcast units, by obtaining patent and copyright protection.
While patent and copyright protection offer a substantial amount of protection, detecting infringement of these rights is difficult. Many manufacturers discover that one of their patented or copyrighted products has been infringed through advertisements of competitors, from customers, or from their sales force. Each of these methods are limited in that the manufacturer is reliant on informants to discover the infringement. In essence, these methods don't offer an active way of discovering infringement. Therefore, a need exists that allows manufacturers, especially those that manufacture communication and/or broadcast units, to actively detect when their patented and/or copyrighted products have been infringed.